This is the first English translation of the ground-breaking study by the German medical doctor, psychotherapist, and mystic Carl Albrecht (1902-1965), first published in 1951 as Psychologie des Mystischen Bewußtseins. The book, reprinted in Germany in 1976, 1990 and 2018, has remained untranslated to date and is now made available to international scholarship in an annotated English edition. The book offers the results of Albrecht's meticulous long-term empirical research into mystical consciousness.